Refrigerating apparatus with charging plug



Feb. 22, 1949. l1. M. MURPHY 2,462,535

REFRIGERATING APPARATUS wn'n pmmsme PLUG Filed Jilly 3, 1946 FIG. 4

for sealing the refrigeran Patented Feb- 1949 aamrcanarma mums wrrn crmncma PLUG John M. Murphy, Dayton,

Ohio, asaignor to General Motors Corporation, Dayton, Ohio, at

corporation of Delaware Application July 3, 1946, Serial No. 681 ,249

This invention relates to refrigerating apparatus and more particularly to an improved arrangement for charging a refrigerating system with refrigerant and lubricant.

One object of this'invention is to Provide an improved charging connection which makes .it possible to supply refrigerant to both the high side and the law side of the system simultaneously. l

A further object of this" invention is to provide a charging connection without developing any leaks.

, A still further object of this invention is to provide a multiple passage charging connection having a single closure member for both passages.

A still further object of this invention is to provide an improved chargingconnection which is easy to open and close.

Further objects and advantages of the present invention will be apparent from the following description, reference being had to the accompanying drawings, wherein a preferred form of the present invention is clearly shown.

In the drawings:

Fig. 1 is a diagrammatic view of a refrigerating system embodying my inventio Fig; 2 is a plan view of the charging connection on an enlarged scale;

' Fig. 3 is an enlarged sectional view taken on line 3-3 of Fig. 1;

Fig. 4 is an end view of the cap which is used charging passages; and,

Fig; 5 is a sectional view of the cap.

Referring now to Fig. 1 of the drawing in which I have shown a preferred embodiment of my invention, reference numeral Ill designates nerally a sealed motor compressor unit and reference numeral l2 designates a substantially cupshaped stamped sheet metal casing which forms the main support for the compressor assembly H. A motor I6 is used for operating the compressor [4 in accordance with standard practice. A stamped sheet metal end cap l8 closes the upper end of the cup-shaped casing element l2 and forms therewith a high pressure refrigerant vapor chamber into which the compressor l4 discharges the compressed refrigerant. The end cap I8 is welded 'or otherwise secured to the main casing l2. The compressed refrigerant leaves the casing I! through the outlet line l9 which leads to the condenser in which the refrigerant is condensed. The condensed refrigerant collects in the receiver 22 from whence it flows to the evaporator 24 through a conventional refrigerant flow concapable of repeated use '2 Claims. (01. 62-115) trol device 28. The refrigerant flow control device may be of any conventional construction and is preferably of the fixed restrictor type in which the high pressure liquid refrigerant is required to flow through a long narrow capillary passage so as to have its pressure reduced prior to entry into the evaporator 24. The refrigerant vaporized in the evaporator 24 returns to the compressor though the line 28 which communicates with the passage 30 formed in the adapter block 32. A screen element 34 is arranged directly within the passage 30 and serves to stop the flow of soli particles into the main compressor. The 11 "per side of the adapter block 32 is provided with a recess 38 in which a check valve assembly 38 is mounted. The check valve assembly 38 may be of any conventional construction and is preerat;,

held in place by means of the lower end plate as of the compressor l4. The compressor and plate 50 rest upon the upper surface of the adapts.- block 32 and one or more mounting blocks 39 which are welded or otherwise secured to the bottom wall of the casing l2.

The compressor assembly i4 comprises the lower end plate 50, the cylindrical element 52,

and an upper end plate 54' which has formed intervally therewith the main bearing 55 in which the main shaft 51 is journaled. The upper end plate 54 is provided with a conventional discharge outlet 60. An impeller 62 is provided within the cylinder 52 and is arranged in engagement with the eccentric portion 64 of the shaft 51 which causes the impeller to compress refrigerant within the cylinder 52in accordance with well-known practice. A divider block 66 cooperates with the cylinder 52 and the impeller 62 so as to separate the high pressure gas from the low pressure gas. A spring 68 which is held in place by the spring retainer 10 biases the divider block in engagement with the impeller 62.

The adapter block 32 is provided with a refrigerant charging plug 84 which comprises an outer cylindrical element 86 and an inner cylindrical or tubular element 88 spaced from the outer cylindrical element 86 by means of a plurality of spacer elements 90 as best shown in Fig. 3. The inner end of the tube 88 is hydrogen brazed to the disk 92 through which the tube 88 projects so as to communicate directly with the low side passage 30 formed in the adapter 32. The passage 94 formed between the outer cylindrical element 88 and the inner tube 88 communicates with the high pressurev chamber 95 within the adapter block 32. A passage 98 connects the chamber 95 with the compressed gas in the main snoasss motor-compressor casing ii. The lower end plate so of the compressor is cut away as at 88 so as to provide a passage from the high pressure gas within the chamber I: to the passage 98 in the adapter block 32. The charging plug and adapter parts are preferably subjected to a hydrogen brazing operation after assembly so as to cause sealing of all the joints.

The outer ends of the cylindrical elements 88 and 8B are machined smooth and are adapted to be closed by means of a relatively soft disk I carried by the removable cap H2. The cap N12 is hexagonal in shape as indicated in Fig. 4 and is provided with a plurality of radial passages I04 through which a refrigerant charge may pass when the cap IE2 is partially unscrewed from the plug 85 so as to retract the sealing disk Hill from engagement with the end surfaces of the tubes 86 and 8 8. By virtue of the above described arrangement it is not necessary to fully unscrew the cap 592 in order to charge the system with refrigerant. Since the smooth end surfaces of the elements 86 and as are concentrically arranged with respect to the center of rotation of the disk I00, repeated use of the charging connection will not cause damage to the sealing disk Hill.

While the plug 86 has been referred to as acharging plug and has been described as such, it is obvious that it may be used for either adding or removing refrigerant and/or lubricant from the system and that it may also be used for purging the system.

While the form of embodiment of the invention as herein disclosed constitutes a preferred form, it is to be understood that other forms might be adopted, as may come within the scope of the claims which follow.

What is claimed is as follows:

1. In a refrigerating system, an evaporator, a refrigerant translating device and conduits connecting said device and said evaporator in closed circuit relationship, said refrigerant translating device including a casing enclosing a compressor, a motor for operating said compressor, said casing having an inlet communicating with said compressor and an outlet, a plug projecting through said casing and being accessible from outside of said casing, said plug comprising a first tubular element and a second tubular tubular element in spaced relationship thereto and forming therewith two separate passages, said first tubular element having externally formed threads thereon, a disc for closing both of said passages, and means holding said disc confined therein and adapted to seal the same against the outer end of said plug, said means comprising an internally-threaded cup-shaped cap located on said externally formed threads on said first named-tubular element of said plug and having a passageway formed in the side wall thereof arranged so as to communicate with both of closed circuit relationship,

said separate passages upon partial removal of said cap from said plug.

2. In a refrigerating system, an evaporator, a refrigerant translating device and conduits connecting said device and said evaporator in said refrigerant translating device including a casing enclosing a compressor, a motor for operating said compressor, said casing having an inlet communicating with said compressor and an outlet, a plug projecting through said casing and being accessible from outside of said casing, said plug havin a first passage communicating with the inlet of said compressor and a second passage arranged concentrically with said first passage and communicating with the outlet of said casing, said plug having externally formed .threads thereon, a disc for closing both of said passages, and means having said disc confined therein and adaptedto seal the same against the outer end of said plug, said means comprising an internally threaded cup-shaped cap located on said externally formed threads on said plug and having element concentrically arranged within said first a passageway formed in the sidewall thereof arranged so as to communicate with said first and said second passages upon partial removal of said cap from said plug. JOHN M. MURPHY.

' REFERENCES orra'n UNI'I'ED STATES PATENTS Number Name Date 1,526,857 Hughes Feb. 1'1, 1925 2,192,572 Bourdon Mar. 5, 1940 2,405,904 Ratalczak Aug. 13, 1946 2,420,442 Rataiczak May 13, 1947 

